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Folks - sorry about the previous "post"-with-no-answer. 
Got a bit ahead of myself!

Anyway - which Hoechst are they using? One is 
cell-permeant (33342), one needs to have some membrane 
disruption before it will enter (33258). I thought the 
permeant version could cross cell walls, but it has been 
ages since I've tried it on anything plantish, so I may be 
mistaken. Maybe they're using 33258?

Tamara

On Wed, 13 Jun 2007 16:42:56 -0400
  "J.P. Shields" <[log in to unmask]> wrote:
> Search the CONFOCAL archive at
> http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal
> 
> Hi everyone,
> I have a colleague asking me why their Aspergillus 
>nidulans won't take up
> Hoechst stain very well until they have fixed briefly 
>(1-2 minutes) in
> formaldehyde/buffer.  Anyone else experienced this 
>problem and (more
> importantly) know why it would be like this?  Off the 
>top of my head, I
> suspect the fixation disrupts the membrane potential, 
>allowing particular
> molecules to enter more readily. However, it could have 
>something to do with
> the chitinous cell wall?
> 
> Thanks!
> John
> 
> John Shields
> EM Lab, 151 Barrow Hall
> Univ. of Georgia
> *******
> Always and never are two words you should always 
>remember never to use.
>  - Wendell Johnson

***************************
Tamara Howard
Cell Biology & Physiology
UNM-HSC
Albuquerque, NM
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